A new study suggests that people who develop dementia tend to have lower body weight and smaller waist sizes years before their diagnosis. The study, published in JAMA Network Open, also found that these individuals had higher levels of good cholesterol (high-density lipoprotein, or HDL) before their condition was identified.
The research, led by Dr. Zimu Wu from Monash University in Australia, looked at health data from a large group of older adults. The participants were part of the Aspirin in Reducing Events in the Elderly study, which was designed to examine the effects of aspirin on aging.
Scientists compared 1,078 people who were later diagnosed with dementia to 4,312 similar individuals who did not develop the condition. The two groups were matched based on factors like age and background to ensure a fair comparison.
The results showed clear patterns. People who later developed dementia had a lower body mass index (BMI) and smaller waist size for at least seven years before their diagnosis.
This difference was even more noticeable in the ten years leading up to their condition, as their BMI and waist size declined at a faster rate compared to those who did not develop dementia. This suggests that unexplained weight loss, even in older adults who appear healthy, might be an early sign of cognitive decline.
The study also found that people who developed dementia had higher levels of HDL cholesterol, especially in the five years before their diagnosis. However, these levels started to drop closer to the time dementia was detected.
Other changes in cholesterol levels were also observed. People with dementia had slightly higher levels of low-density lipoprotein (LDL, or “bad” cholesterol) and total cholesterol compared to the control group, but these differences were not significant.
Blood pressure and fat levels in the blood also followed unusual trends. The research found that people who later developed dementia had lower systolic blood pressure and lower triglyceride levels in the decade leading up to their diagnosis.
Triglycerides are a type of fat in the blood that is usually linked to heart disease. While high triglycerides are considered unhealthy, this study suggests that unusually low levels may also be linked to dementia.
The researchers believe these findings show that certain changes in weight, cholesterol, and blood pressure may serve as early warning signs of dementia.
However, they are not yet sure if these differences cause dementia or if they are simply symptoms of the disease developing over time. It is possible that the brain changes associated with dementia also affect metabolism and other bodily functions.
One key takeaway from this research is that monitoring changes in weight and cholesterol over time could help doctors identify people at higher risk of developing dementia. Instead of focusing only on risk factors like obesity and high cholesterol, doctors might also need to pay attention to unexpected weight loss and declining cholesterol levels in older adults.
The study does have some limitations. It does not prove that these changes cause dementia, only that they are linked to the condition. Also, some of the researchers involved in the study have connections to the pharmaceutical industry, which should be considered when interpreting the results.
Despite these limitations, the findings add to growing evidence that dementia is not just a brain disease but may also be linked to broader changes in the body. More research is needed to understand exactly how these changes occur and whether they can be used to develop better prevention strategies.
If you care about brain health, please read studies about Vitamin B9 deficiency linked to higher dementia risk, and cranberries could help boost memory.
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The research findings can be found in JAMA Network Open.
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